[PATCH RFC 55/77] ntb: Update MSI/MSI-X interrupts enablement code

Alexander Gordeev
2013-10-02T10:49:11Z

As result of recent re-design of the MSI/MSI-X interrupts enabling
pattern this driver has to be updated to use the new technique to
obtain a optimal number of MSI/MSI-X interrupts required.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
---
drivers/ntb/ntb_hw.c | 41 +++++++++++++----------------------------
drivers/ntb/ntb_hw.h | 2 --
2 files changed, 13 insertions(+), 30 deletions(-)

diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c
index eccd5e5..7776429 100644
--- a/drivers/ntb/ntb_hw.c
+++ b/drivers/ntb/ntb_hw.c
@@ -1032,23 +1032,26 @@ static int ntb_setup_msix(struct ntb_device *ndev)
struct msix_entry *msix;
int msix_entries;
int rc, i;
- u16 val;

- if (!pdev->msix_cap) {
- rc = -EIO;
+ rc = pci_msix_table_size(pdev);
+ if (rc < 0)
goto err;
- }

- rc = pci_read_config_word(pdev, pdev->msix_cap + PCI_MSIX_FLAGS, &val);
- if (rc)
+ /*
+ * On SNB, the link interrupt is always tied to 4th vector. If
+ * we can't get all 4, then we can't use MSI-X.
+ */
+ if ((rc < SNB_MSIX_CNT) && (ndev->hw_type != BWD_HW)) {
+ rc = -ENOSPC;
goto err;
-
- msix_entries = msix_table_size(val);
- if (msix_entries > ndev->limits.msix_cnt) {
+ }
+ if (rc > ndev->limits.msix_cnt) {
rc = -EINVAL;
goto err;
}

+ msix_entries = rc;
+
ndev->msix_entries = kmalloc(sizeof(struct msix_entry) * msix_entries,
GFP_KERNEL);
if (!ndev->msix_entries) {
@@ -1060,26 +1063,8 @@ static int ntb_setup_msix(struct ntb_device *ndev)
ndev->msix_entries[i].entry = i;

rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);
- if (rc < 0)
+ if (rc)
goto err1;
- if (rc > 0) {
- /* On SNB, the link interrupt is always tied to 4th vector. If
- * we can't get all 4, then we can't use MSI-X.
- */
- if ((rc < SNB_MSIX_CNT) && (ndev->hw_type != BWD_HW)) {
- rc = -EIO;
- goto err1;
- }
-
- dev_warn(&pdev->dev,
- "Only %d MSI-X vectors. Limiting the number of queues to that number.\n",
- rc);
- msix_entries = rc;
-
- rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);
- if (rc)
- goto err1;
- }

for (i = 0; i < msix_entries; i++) {
msix = &ndev->msix_entries[i];
diff --git a/drivers/ntb/ntb_hw.h b/drivers/ntb/ntb_hw.h
index 0a31ced..50bd760 100644
--- a/drivers/ntb/ntb_hw.h
+++ b/drivers/ntb/ntb_hw.h
@@ -60,8 +60,6 @@
#define PCI_DEVICE_ID_INTEL_NTB_SS_HSX 0x2F0F
#define PCI_DEVICE_ID_INTEL_NTB_B2B_BWD 0x0C4E

-#define msix_table_size(control) ((control & PCI_MSIX_FLAGS_QSIZE)+1)
-
#ifndef readq
static inline u64 readq(void __iomem *addr)
{
--
1.7.7.6